1. Field of the Invention
The present invention, in general, relates to motor vehicles and, more particularly, to the exhaust sound produced by automobiles or other types of motor vehicles.
Having internal combustion engines, motor vehicles have, since their inception, produced an audible and, at times, distinct exhaust sound. The sound that is produced often varies from automobile to automobile. For example, the exhaust sound from an eight cylinder muscle car, such as an old CHEVROLET CORVETTE, is quite different than the exhaust sound of a modern FERRARI.
The exhaust sound that an automobile produces is important to many people. When the MIATA model was introduced, MAZDA MOTOR COMPANY as the maker of the MIATA, claimed to have tried over 200 different exhaust configurations in an attempt to obtain an optimum sounding exhaust system.
Many people have developed a general preference for how an automobile should ideally sound. For example, some people prefer the sound of twelve cylinder relatively high RPM automobile engines while other prefer the deeper sound of low RPM large displacement engines. In fact, the sound of a particular vintage automobile may have become associated with a period in a person's life and, upon again hearing that sound, it may trigger fond memories and thereby, even cause an uplifting of spirit. That person may indeed long for an automobile that produces the particular exhaust sound of some vintage, classic, or unusual automobile.
However, that is difficult to achieve. Vintage, classic, or exotic automobiles are in limited supply and are far too expensive for most people. With today's available automobiles, many of the models have similar identical power plants (i.e., engines). Accordingly, there may be little difference in the sound among the many models that are available. Even among the various models there may not be an appreciable difference in the sound from one manufacturer to another.
As a result people spend a good deal of money purchasing after-market exhaust systems in order to endow their particular car, truck, or motorcycle with a unique sound that they hope will be pleasing to their ears and also pleasing to the ears of others.
The problem is that they cannot know ahead of time what the after-market exhaust system will sound like on their particular motor vehicle until after they have purchased it and installed it. Then, if they do not like the sound it produces they are basically bound to endure it or replace it with yet another after-market exhaust system. If the first exhaust system is replaced, then its entire cost is typically absorbed by the end-user; not a pleasant situation.
The maximum legal volume permitted for a motor vehicle's exhaust sound (i.e., pressure) is generally regulated for all vehicles that are used on public roads and highways. Regulations may be set by local governments, the state, or the Federal government. These regulations limit the sound pressure (i.e., volume) that most vehicles can produce.
Many after-market exhaust systems are louder than stock exhaust systems and some after-market exhaust systems may, at times, exceed permissible maximum volume levels (typically measured in decibels). As used herein, the term “after-market” is broad and includes any exhaust system component that may replace or be added as an additional component to an existing (i.e., stock) exhaust system.
Many people prefer a more robust sound to their exhaust and may be inclined to put a louder after-market exhaust system on an automobile that is used on public roads. Doing so places them at risk for citation and fine.
For all exhaust systems, stock or after-market, the sound volume of the exhaust is not in any practical way, adjustable. This is because the volume that an exhaust system produces is not a user-controllable variable, other than how it relates to RPM and load.
For virtually all automobiles, the volume (sound pressure) varies with the speed of the engine and the load upon the engine. For any given engine, the exhaust volume typically rises with an increase in engine speed (RPM) and lowers with a lessening of engine speed. The exhaust volume also typically rises with an increase in load upon the engine. For example, most automobile engines will produce a louder exhaust sound when the engine reaches high RPM during acceleration than it would at the same high RPM but under no load, such as when the vehicle is in neutral.
Whether the vehicle is accelerating or decelerating also matters. Many vehicles produce an entirely different sound depending upon whether the vehicle is accelerating or decelerating. Some vehicles may even backfire and produce a louder sound (i.e., greater sound pressure) when decelerating rather than accelerating.
With conventional exhaust systems it is not possible to effectively control the volume of exhaust by a control of load and engine speed because normal driving conditions vary and impose various loads upon an engine during use. In other words, if a person had an exhaust system that, at times, was too loud (i.e., not “street-legal”), the person could not merely drive at idle or very low engine speeds when on public roads to lessen the volume of exhaust sound. At times, the driver would have to accelerate in order to reach a safe driving speed comparable to that of other vehicles, thereby raising the exhaust volume beyond an acceptable level.
Yet, a long-standing need to vary the volume of exhaust (i.e., engine sound) does exist. A person driving on a busy city street would not want their exhaust sound to be excessively loud, less they attract undo attention and possibly receive a citation. However, when the same person was pleasure-driving the same motor vehicle on a remote rural road he or she might prefer a louder exhaust sound. With both stock and after-market exhaust systems, this has, heretobefore, been impossible to attain.
The exhaust sound is also useful in alerting pedestrians of the approach of a motor vehicle. As such, there is benefit in being able to audibly detect an approaching automobile. For example certain of the newer electric or hybrid automobiles, when running only on electricity, are very nearly silent in operation.
This has caused problems because people, unaware of their approach, have entered into the path of an approaching and especially quiet automobile. This is a problem for normally sighted people and can be especially serious for the visually impaired. As a result, a motor vehicle that is too quiet is, at times, dangerous and this realization has prompted the consideration of legislation intended to require that motor vehicles produce some sort of an audible sound.
There has, heretobefore, been no aesthetically acceptable way of producing an acceptable sound, such as an exhaust sound, for motor vehicles that is both pleasing to the ear and of appropriate volume so as to be useful in warning pedestrians of the approaching vehicle at a safe distance.
Also, there is the problem of acclimation and boredom. People get used to the way their automobile sounds and, consequently, their ability to enjoy the sound of their vehicle diminishes with time. This is the result of becoming acclimated to the vehicle's sound and the result is a loss of awareness. Drivers may genuinely enjoy the way their vehicle sounds and over the course of time the same sound that at one time delighted their senses may become boring and even monotonous. Ideally, a driver would want to vary the character of exhaust so that it replicates the exhaust sound produces by different vehicles from time to time.
The ability to instantaneously change the character of exhaust sound and its volume have not been satisfied by any of the prior art solutions.
Sometimes, the driver may want to alter the sound that is heard primarily in the cockpit (i.e., in the interior) of the automobile and not that which is heard by others, for example, by pedestrians as the vehicle passes by. At other times, the driver may want to alter the sound that is produced by the vehicle and which others hear. Still, at other times the driver may want a combination of the two whereby the sound that is produced in the vehicle's interior is varied at the same time that the exterior sound that is produced externally is also varied.
This is because the exhaust sound that a driver typically hears is a combination of sounds. It includes sounds that are coming directly from the engine compartment as well as sounds that are coming from the exhaust. Depending on the type of vehicle the balance of these sounds can vary. For example, with roadsters and convertibles a larger percentage of the sound that is heard by the driver will typically emanate from the exhaust while for certain sedans it may include more of the engine sounds coming from the engine compartment.
It is desirable to allow driver's to enjoy whatever sound combination they prefer and to be able to direct that sound primarily in the interior of the vehicle or externally or both.
The characteristic sound of an automobile is a variable, as was previously mentioned, because it varies with engine speed and with load. Therefore, it has not been possible to effectively replicate the exhaust sounds of different motor vehicles for use in a dynamic environment.
In other words, if a particular vintage automobile's exhaust sound was recorded and played through an automobile's stereo system, this would not be pleasing to a user of such a system because the sound that is being heard would not correlate to what the automobile is doing. A driver would not appreciate listening to the vintage car accelerate while they were idling at a stop light, nor would they appreciate the sound of the vintage car at idle while they were accelerating.
To be realistic, the sound that is produced must be synchronized with the engine speed of the vehicle in which it is heard.
Additionally, it would be even more realistic if it were synchronized and adjusted accordingly with the load of the motor vehicle in which it is overlaid.
For example, if a driver is listening to the recorded sound produced by a vintage automobile while driving a personal vehicle, the vintage vehicle's sound must match the engine speed of the personal vehicle. If the personal vehicle is decelerating, it is desirable that the sound the driver hears reflect that of the vintage vehicle when the vintage vehicle is decelerating. Conversely, if the personal vehicle is accelerating, it is desirable that the sound the driver hears reflect that of the vintage vehicle when the vintage vehicle is accelerating.
It is desirable at times to have the exhaust volume that is externally audible (i.e., to pedestrians) quiet while the exhaust sound that a driver hears in the cockpit (i.e., interior) is loud. The driver may want to enjoy listening to a loud replicated engine sound that only they hear without disturbing those who are external to the vehicle. This has, heretobefore, been impossible to attain.
The need to make an automobile sound different is not confined to making it sound only like other automobiles. For example, a pilot might want to make his personal vehicle (car) sound like a P51 Mustang or some other type of current or vintage airplane. Similarly, a boating enthusiast might want to make his personal vehicle sound like a vintage boat, for example, an old Chris Craft. Continuing the need, a motorcycle enthusiast might want his personal vehicle to sound like a Harley-Davidson or some other vintage motorcycle.
It is also important to note that the exhaust system and its output may be regulated, as previously mentioned, by local, state, or Federal laws, whereas an audio output may not be regulated or it may not be regulated in the same manner. While it may be prohibited to modify the exhaust system for certain types of vehicles or it may be prohibited to make modification to the exhaust system that increases the volume of the exhaust noise produced it may be permissible to include an audio output of any preferred volume that replicates exhaust sound and thereby accomplishes the desired effect without infraction of any laws.
All of the prior art solutions to this date have failed to adequately satisfy various important requirements as described above and below and, as a result, a desirable solution is not yet commercially available.
As an example of various additional needs that have not been satisfied, there is a need for both rapid and uncomplicated installation. Ideally, the device would require it being plugged into a single connector in the vehicle and be ready for use.
If communication between the device and a stereo system in the vehicle were wireless, then the need to run electrical cables and pay for complicated or expensive electrical wiring would be eliminated.
Ideally, such a device could be installed directly by the user, or alternately, by those with minimum technical expertise.
Additionally, there is a need to use existing technology devices as platforms. This can reduce the cost of such a device when the user already has such a platform available. For example, the IPHONE™ is a popular device that could be used as a platform. Similarly, the IPOD TOUCH™ is another popular device that could be used as a platform.
Accordingly, there exists today a need for an engine sound replication device that helps to ameliorate the above-mentioned problems and difficulties as well as ameliorate those additional problems and difficulties as may be recited in the “OBJECTS AND SUMMARY OF THE INVENTION” or discussed elsewhere in the specification, or which may otherwise exist or occur and are not specifically mentioned herein.
Clearly, such an apparatus would be a useful and desirable device.
2. Description of Prior Art
Exhaust systems of all types are, in general, known. Engine monitoring equipment is also, generally, known. For example, the following patents describe certain types of engine monitoring devices:
U.S. Pat. No. 6,973,377 to Majstorovic et al., that issued on Dec. 6, 2005;
U.S. Pat. No. 7,013,207 to Majstorovic et al., that issued on Mar. 14, 2006; and
The entire specification of U.S. Pat. No. 6,973,377 is hereby incorporated by way of reference herein as a part of this specification.
The entire specification of U.S. Pat. No. 7,013,207 is hereby incorporated by way of reference herein as a part of this specification.
These prior art references teach devices and methods of obtaining acceleration and RPM data from an engine that is useful with the present invention.
Additionally, U.S. Pat. No. 5,835,605 to Kunimoto that issued on Nov. 10, 1998 teaches an exhaust sound synthesizer that is used with flight simulators and computer games but which differs from the instant invention in material ways. For example, it does not include a memory library of engine sounds from a variety of predetermined vehicles but instead includes one basic exhaust waveform that is taken at different periods and which is selected depending on speed information supplied by a joystick or acceleration pedal of the game. The selected waveform is then subjected to an exhaust pipe circuit that appears to introduce delays and reverberation into the waveform and thereby synthesize an output that sounds like exhaust operating through one particular muffler (i.e., tailpipe). In short, it is a synthesizer and not a replication device of engine sounds and thereby teaches away from replication.
Additionally, US Patent Application Number 20050259830 is for a sound enhancement for a single engine sensor and thereby does not include the memory library and other elements of the instant invention as mentioned in the previous comparison with the known prior art.
Other related prior art patents and publications include:
U.S. Pat. No. 6,356,185 to Plugge et al., Mar. 12, 2002;
U.S. Pat. No. 5,820,442 to Helder, Oct. 13, 1998;
U.S. Pat. No. 5,237,617 to Miller, Aug. 17, 1993;
U.S. Pat. No. 7,203,321 to Freymann et al., Apr. 10, 2007;
U.S. Pat. No. 7,088,829 to Schick et al, Aug. 8, 2006;
U.S. Pat. No. 6,959,094 to Cascone et al, Oct. 25, 2005;
U.S. Pat. No. 6,859,539 to Maeda, Feb. 22, 2005;
U.S. Pat. No. 6,725,150 to Glandian, Apr. 20, 2004;
U.S. Pat. No. 6,275,590 to Prus, Aug. 14, 2001;
U.S. Pat. No. 5,734,726 to Truchsess, 1998;
U.S. Pat. No. 5,692,052 to Tanaka et al, Nov. 25, 1997;
U.S. Pat. No. 5,635,903 to Koike et al, Jun. 3, 1997;
U.S. Pat. No. 5,371,802 to McDonald et al, Dec. 6, 1994;
Patent publication US 2005/0259830 to Vaishya, Nov. 24, 2005;
Patent publication US 2007/0147626 to Casey et al., Jun. 28, 2007;
While the structural arrangements of the above described device may, at first appearance, have certain distant similarities with the present invention, it differs in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with any of the known prior art devices.